The Rubicon tires have an overall diameter of a hair over 32". The base X tires have an overall diamater of about 29.3". That's a difference of 2.7". Half of that would contribute to increased clearance. That's 1.35". The Jeep website lists 1.4". Seems reasonable to me.

The Rubicon tires have an overall diameter of a hair over 32". The base X tires have an overall diamater of about 29.3". That's a difference of 2.7". Half of that would contribute to increased clearance. That's 1.35". The Jeep website lists 1.4". Seems reasonable to me.

The Rubicon tires have an overall diameter of a hair over 32". The base X tires have an overall diamater of about 29.3". That's a difference of 2.7". Half of that would contribute to increased clearance. That's 1.35". The Jeep website lists 1.4". Seems reasonable to me.

I think your measurement is too conservative. I have the Ravine wheels with 30x9.5x15 on my 2004 TJ. I bought a 2005 Rubi Moab take-offs with 31" tires. When I stood the spare tire next to my 30", the 31" tire stood a full 3 inch taller than the 30" I have. This means 1.5" higher axle height. So, it could be more than 2.7 inch.